Printing systems and methods typically employ three or four color ink sets of cyan, magenta, yellow and optional black inks that together must be able to reproduce accurately many of the visible colors. In ink jet printing, the inks are applied dropwise to a substrate, in a pixel-by-pixel manner, with the number of printed dots corresponding to the density required for a particular imaged area. Thus, an ink jet printer that employs a three or four color ink set prints relatively few dots in low density areas, as compared to high density areas. Image quality is often compromised because in very low density areas, sparsely printed dots of color from three or four color ink sets are noticeable on a white substrate. In addition, highlight areas often lack detail because not enough dots are printed.
In order to improve image quality, ink jet printers may utilize additional “light” inks together with the inks of three or four color ink sets. For example, the most common ink set having light inks is the six color ink set which has light cyan, light magenta, cyan, magenta, yellow, and black inks. Typically, the light inks are the same as the regular inks, sometimes referred to as “dark” inks, except that the light inks have less of the same colorant. More dots in low density areas may be printed with the light inks as compared to the dark inks of regular strength in order to achieve the same density. As a result of printing more dots of lower contrast, image quality is greatly improved.